Bookfinder was vol 1& 2 for $485
On Sunday, March 14, 2021, 03:29:29 PM CDT, Dave Daniel <kc0wjn@...> wrote:
bookfinder. com finds sone copies of Lawson. Somewhat expensive second-hand (but not $500!).
DaveD
On Mar 14, 2021, at 16:14, David Kirkby <
drkirkby@...> wrote:
On Sun, 14 Mar 2021 at 01:47, Reginald Beardsley via <pulaskite=
[email protected]> wrote:
If anyone knows of a rigorous proof that the Yagi-Uda is the "sharpest beam" I am *very* interested in reading it.? On inspection it seems plausible, but mathematics at that level is rather a black art to mere applied math people like me.
Thanks and..
Have Fun!
Reg
I find it extremely unlikely that such proof exists. You would of course need to start by defining what is the "sharpest beam". The diffraction limit puts a limit on the first sidelobe and some Yagi-Uda antennas have the first sidelobe approximately that.
I find it worrying that the ARRL no longer sell Lawson's book on Yagi-Uda antennas. It was an ARRL publication.? It was the book that taught me enough to write my own program to analyze the antenna. It is a fairly different concept to NEC. You could argue it give you an analytical expression for the far-field, as the far-field pattern depends on the self impedance of elements and the mutual impedance between them. But the formula for mutual impedance in Lawson's book makes the assumption the elements have zero diameter and are a half-wave long.
The National Bureau of Standards (NBS)? made lots of careful measurements on Yagi-Uda antennas. Lawson shows that one of them must be wrong - probably just a typo.
Dave
